Vegetation has been utilized to provide aesthetic value and soil stabilization for many years. One particular problem with vegetation is the time that it takes for the vegetation to propagate and/or root into the soil. Seed germination suffers from the deficiencies of slow root growth and inadequate water retention. To facilitate vegetation growth, prefabricated seed carriers were developed, such as disclosed in for example, U.S. Pat. No. 2,648,165 to Nestor; U.S. Pat. No. 2,826,865 to Chohamin; U.S. Pat. No. 2,909,003 to Marshall; and U.S. Pat. No. 3,914,901 to Muldner.
Seed carriers are well known in the art and often suffer from problems in that they are difficult to handle, contain non-biodegradable components, contain non-homogenous mixtures, suffer poor water retention characteristics, and have a poor shelf life.
Many of the seed carriers developed have utilized synthetic nettings, woven and other sheet materials as support media. Nettings often are too weak to provide sufficient soil stabilization, have a tendency to tear during application, and are otherwise generally difficult to handle. The synthetic materials are expensive, and, being non-degradable, tend to be raised by vegetation growing beneath. The netting can become dislodged by increased traffic and high winds. Eventually the netting must be removed by hand and often effective control of erosion ceases.
In an effort to expedite the bio-degradation of the support media, seed carriers utilized biodegradable materials such as light paper as backing material, for example, as in U.S. Pat. No. 4,173,844 to Knolle et al.; and U.S. Pat. Nos. 4,190,981 and 4,318,248 to Mulder.
U.S. Pat. No. 4,283,880 to Fjeldsa discloses a “peat paper” wherein sphagnum peat moss is utilized as a vector material for seeds.
Existing nettings have been employed or suggested for use in applications such as landscaping, highway construction and maintenance, and strip mine recovery. With the possible exception of certain landscaping applications, all such cases require a system needing little maintenance once the area covered by the netting is planted. It would be highly desirable to have a product that would degrade completely, allow full development of vegetation, and provide substantial erosion control.
U.S. Pat. No. 4,786,550—McFarland et al.—disclose the use of melt-blown and coform materials to produce an artificial seedbed. The seedbed is comprised of a combination of seeds, fertilizers, herbicides, superabsorbants, and coform, which is the combination of cellulose fibers and a suitable polymer such as polyethylene or polypropylene. While this combination provides for an appropriate seedbed, the biodegradation time remains high due to the polymer contained therein.
Cellulose fibers and cellulose-based materials have been used to manufacture artificial seedbeds for some time, while these materials are beneficial, they have always been used with other synthetic materials which lengthen biodegradation or held together by a woven material or web. Therefore, there remains a need for an artificial seedbed that is stable during the time of seeding, degrades within a reasonable time, does not contain synthetic fibers, and provides protection and nourishment to the seed during germination and sprouting.